Vaporizing with a vape pen or another device offers the same immediate benefits of smoking. But since a vaporizer heats the cannabis flower or oil without burning it, the active ingredients are inhaled as a vapor and no smoke is involved. This makes it a healthier alternative to smoking. When inhaled, CBD is absorbed by the lungs, into the blood, and cross the blood-brain barrier. The first effects of inhaled cannabis usually occur within a few minutes, and gradually wear off after 2-3 hours. Vaping is often effective for treating acute symptoms that need to be addressed quickly, such as painful spasms, nausea, and vomiting. It is fairly easy to titrate the dose by inhaling. If the effect is insufficient after a few minutes, one can take another puff until the desired effect is achieved. But vape may contain noxious substances that may irritate the lungs.